A major challenge in modern biology and nanotechnology is to observe, identify and differentiate a large number of different molecular species in real time. Fluorescent microscopy is a powerful tool for non-destructively and dynamically monitoring many individual molecular events. However, the multiplexing ability of fluorescent imaging is limited by the number of spectrally non-overlapping fluorophores available. There is therefore a great need for novel addressable fluorescent probes useful in multiplex detection systems.